Responsive Buildings Skins: Daylight and Energy Analysis of Smart Thermo Bi-metal Systems

The building envelope significantly influences thermal comfort, daylighting, and heating and cooling loads  in buildings. Over the past few decades, facade designs have evolved through the application of  environmental simulations and algorithms. The typical approach to high-performance facades through  single or multi-parameter optimization towards specific performative goals, while calculated for  efficiency, does not address changing environmental factors and transient user needs. In contrast,  adaptive façades, capable of responding to variable boundary conditions and shifting performance goals  by periodically and reversibly altering their behavior, have emerged as a strategy to optimize building  performance. However, many contemporary kinetic facades suffer from complexity due to mechanical  parts, which are challenging to maintain, prone to breakdown, and require energy to operate.   

There is a need to explore how the complexity of kinetic façades can be simplified while still optimizing  for daylight and energy use. A growing body of research advocates for the use of ‘smart materials’ in  façade design. These systems utilize the intrinsic properties of the material to produce a change in  geometry in response to an external environmental factor such as light, heat, humidity, pressure, and  wind velocity.  

This research explores the effectiveness of temperature-responsive smart materials, specifically thermo  bi-metals, as an alternative to mechanically controlled kinetic facades, focusing on environmental  performance and occupant satisfaction. It aims to develop a digital workflow to simulate the real-time  behavior of such facades using climate data to analyze daylight performance. The study investigates how  module design and patterning logic affects daylighting metrics, comparing the dynamic behavior of a  facade designed with the material against its static state. Immersive reality technology is used as an  experiential tool to understand the qualitative impacts of the facade design on daylighting. The study also  examines how occupant control of these adaptive facades can be implemented through manual overrides  and assesses the potential impacts of these overrides on energy performance.   

The goal of this research is to streamline the design and daylight analysis of adaptive facades using smart  thermo bi-metal systems. Considering, environmental performance evaluation of these systems is sparse  in the current research, it can create a framework for designers to integrate such façade systems in the  early design phase.